Tubular bag provided with an openable tubular bag body

ABSTRACT

Tubular pouch (10), having a tubular pouch body (11) and a lid piece (12) and optionally having a base. The tubular pouch body (11) is formed by means of a fin-seal (14), with at least one weakness of material (16, 17) extending, starting from the free longitudinal edge (15) of the fin-seal (14), around the circumference of the tubular pouch body (11) so that, as required, the tubular pouch (10) can be opened along that weakness of material (16, 17).

The invention relates to a tubular pouch having a tubular pouch body and a lid piece and optionally having a base, especially a stand-up or standing base.

Tubular pouches of the kind under consideration herein are generally known and are used for holding, storing and transporting liquid, paste-form, powdered, pourable and solid contents. They are distinguished by being of very low weight and being easily shapeable and printable. Furthermore, if a suitable material is chosen, they can be disposed of in a simple and environmentally friendly way. More especially, once empty they can be folded down to a minimum volume and disposed of by the appropriate route.

A general problem, however, is the opening behaviour of such tubular pouches or tubular pouch packagings. Such packagings are usually opened by tearing open the packaging, it being usual to provide a gripping point on a sealing seam for that purpose so that the latter can be pulled apart for the purpose of opening, the seal being intended to break open. A disadvantage of that solution, however, is that the packaging is opened in a relatively undirected and uncontrolled way, so that the contents of the packaging are spilled, which, particularly in the case of liquid or pourable contents, frequently results in loss of the packaged goods. Furthermore, after such tearing-open, the interior of the tubular pouch is generally only very poorly accessible, because torn or residual portions of the packaging cause an obstruction and make it difficult to gain access to the interior of the tubular pouch, for example with a spoon. Even when the contents of the packaging are poured out, residual portions of the packaging are very troublesome and, furthermore, result in contamination by the environment, which is often undesirable.

A further variant of opening comprises the use of a pair of scissors by means of which an upper portion of the closed tubular pouch is cut off and removed, so that the contents of the tubular pouch are accessible. Although that variant enables a tubular pouch portion that closes the tubular pouch to be cleanly separated, it creates the problem that it is necessary always to have a pair of scissors to hand. Here too there is a risk that, if the scissors used are not clean, the cut edges of the tubular pouch and possibly also the contents of the tubular pouch will be contaminated and potentially become unusable as a result.

The problem underlying the present invention is to provide a tubular pouch of the kind mentioned at the beginning which can be opened hygienically, simply and without aids, so that the interior of the tubular pouch is accessible without problems. Above all, the opening should be distinguished by a defined opening edge that is free of irregularly protruding portions of the packaging. Finally, the construction according to the invention should provide an opening which is as large as possible and which allows troublefree access to the interior of the pouch with a spoon or the like.

That problem is solved by a tubular pouch or a tubular pouch packaging in accordance with the characterizing clause of claim 1.

A key aspect of the present invention is therefore that the tubular pouch body, which is usually of cylindrical construction, is formed by means of a fin-seal, with at least one weakness of material extending, starting from the free longitudinal edge of the fin-seal, around the circumference of the tubular pouch body so that, as required, the tubular pouch can be opened along that weakness of material, especially over the entire cross-section of the tubular pouch body or tubular pouch. It is thus possible in a simple way to produce a maximum opening of the tubular pouch for the purpose of emptying same. The tubular pouch is therefore opened not by removing the lid piece and/or the base but by dividing the tubular pouch body. Preferably, the weakness of material is located close to the lid piece of the tubular pouch, so that after the tubular pouch has been opened its contents remain reliably and readily accessible in the portion of the tubular pouch body that includes the base.

Opening the tubular pouch is effected by gripping and pulling on the fin-seal in the region of the weakness of material, so that the weakness of material is broken open either only over a circumferential portion or, preferably, around the entire circumference of the tubular pouch body.

The weakness of material is preferably a stamped line that extends continuously or is of non-continuous configuration like a perforation. Ready-made lines of material weakness can be formed without problems, especially by stamping, in the materials customarily used today, especially the laminates preferably used herein. In respect of the materials preferably used herein, reference is made to claim 8.

In an especially preferred embodiment, there are provided two weaknesses of material, especially stamped lines, spaced apart from one another axially and each extending around the circumference of the tubular pouch body, which between them define a tear-open strip which begins at the free edge of the fin seal.

In order to facilitate tearing-open, the weakness of material preferably adjoins a cut formed at the free edge of the fin-seal. That cut can be in the form of a V-notch.

The lid piece and/or the base is/are sealed or adhesively bonded to the tubular pouch body in a conventional way.

As already mentioned, the tubular pouch body is produced from a laminate, especially aluminium laminate, having at least one sealing layer and optionally at least one barrier layer. The barrier layer preferably consists of SiO₂, AlO_(x), ethyl vinyl alcohol or a metal foil.

Furthermore, it can be advantageous for the sturdiness and stability of the tubular pouch for the lid piece and/or the base in each case to be of relatively rigid construction, preferably in the form of a deep-drawn dish having sealable or adhesively bondable rims. Alternatively, the base can also be produced from a laminate and constructed with a V-fold or W-fold, so that the required dimensional stability and sturdiness are likewise obtained.

For reasons of cost it is also advantageous for the lid piece and/or the base to be produced from substantially the same materials as the tubular pouch body.

When the lid piece and/or the base are in the form of a shallow dish it can also be advantageous to provide the surface of the lid piece or base with beads, especially intersecting beads, in order to increase their dimensional stability.

The lid piece and/or the base can also be provided in the form of an injection-moulded part. Ultimately it depends upon the required stability, the size of the packaging and the contents of the packaging.

In respect of the preferred dimensions of the lid piece, the base and the tubular pouch body, reference is made to claim 11.

As required, the lid piece, the base and the tubular pouch body consist of a material that is sterilisable.

An exemplary embodiment of a tubular pouch constructed in accordance with the invention is described below with reference to the accompanying drawing, which shows a perspective view of the half of a tubular pouch constructed in accordance with the invention that is associated with a lid piece. The tubular pouch is constructed like a cylindrical can and has been given reference numeral 10 in the accompanying drawing. It comprises a cylindrical tubular pouch body 11 and a lid piece 12. A base is not shown in the accompanying drawing. The base can, however, preferably be constructed in the same way as the lid piece 12, that is to say in the shape of a shallow dish having a circumferential rim 13 which is sealable to the tubular pouch body 11 at the end thereof. The sealing is effected between the inner edge of the end of tubular pouch body 11 and the outer surface of the circumferential rim 13 of the lid piece 12 or a base of the same construction.

The tubular pouch body 11 is produced from a rectangular laminate, the free longitudinal edges being joined together, that is say sealed, to form a so-called fin-seal 14. Starting from the free longitudinal edge 15 of the fin-seal 14 there are formed, spaced apart from one another axially, two weaknesses of material in the form of stamped lines 16, 17 which extend around the circumference of the tubular pouch body 11 so that, as required, the tubular pouch 10 can be opened along those stamped lines 16, 17. The stamped lines 16, 17 define between them a tear-open strip 18 extending around the circumference of the tubular pouch body 11. In accordance with the accompanying drawing, that strip is located close to the lid piece 12 so that when the tubular pouch 11 is being opened by pulling on the tear-open strip 18 in the direction of arrow 19 substantially only the uppermost portion of the tubular pouch body 11 is removed together with the lid piece 12. The portion of the tubular pouch body 11 that includes the base accordingly is largely retained. To the user the opened tubular pouch has the appearance of having had only the lid piece 12 removed.

The weakness of material, that is to say the stamped lines 16, 17, in each case adjoin a cut formed at the free edge 15 of the fin-seal 14, which cut is in the form of a V-notch 20 in the embodiment shown. Accordingly, the tearing of the stamped lines in the circumferential direction is predetermined and facilitated.

The cross-section of the tubular pouch body 11 can be circular as in the embodiment shown. It is also possible, however, to provide a triangular, polygonal or oval cross-section or the like. In that case, of course, the lid piece and/or the base also need(s) to be adapted accordingly.

As already mentioned at the beginning, the tubular pouch body preferably consists of a laminate. The lid piece and base can be produced from the same material. In respect of the dimensions, it has proved advantageous for the lid piece, the base and/or the tubular pouch body to have a thickness in the range of from 50μ to 500μ, especially from 80μ to 400μ, preferably from 100μ to 350μ.

By using a laminate with unidirectionally stretched foil it is possible for the tubular pouch body to be torn open along the stamped lines 16, 17 in a particularly controlled way. In a unidirectionally stretched foil, the chains of molecules forming the foil are aligned and arranged substantially parallel in the direction of stretching. As a result, the stretched material is able to split preferentially parallel to the direction of stretching in comparison with a direction at an angle thereto, so that oblique tearing through the aligned chains of molecules is rendered significantly more difficult or impossible. When such a foil is split or torn open parallel to the direction of stretching, none of the chains of molecules is severed. Furthermore, none of the chains of molecules is torn out of the molecular structure, because the chains of molecules forming the material are not tangled but are arranged more or less smoothly one next to the other. In that way, tearing such a unidirectionally stretched film parallel to the direction of stretching requires a significantly reduced tearing force in comparison with conventional foils, which force is up to 50 to 60% less than the tearing force that would be necessary for a conventional unstretched or bidirectionally stretched foil. In the embodiment shown, the relevant foil of the foil composite or laminate has been stretched in the circumferential direction, that is to say in the tear-open direction of the tear-open strip 18. In that way, smooth, uniform tear-open edges following the direction of stretching are obtained along the stamped lines 16, 17. In respect of preferred materials and dimensions, reference is made to claims 18 and 19.

All the features disclosed in the application documents are claimed as being important to the invention insofar as they are novel over the prior art either alone or in combination.

REFERENCE NUMERALS

-   10 tubular pouch -   11 tubular pouch body -   12 lid piece -   13 circumferential rim -   14 fin-seal -   15 longitudinal edge -   16 stamped line -   17 stamped line -   18 tear-open strip -   19 arrow -   20 V-notch 

1. A tubular pouch, comprising a tubular pouch body and a lid piece, said tubular pouch body being formed by means of a fin-seal having a free longitudinal edge, wherein at least one weakness of material starts from the free longitudinal edge of the fin-seal and extends around the circumference of the tubular pouch body so that, as required, the tubular pouch can be opened along that weakness of material.
 2. A tubular pouch according to claim 1, wherein the weakness of material is a stamped line selected from the group consisting of a continuously extending stamped line, and a stamped line of non-continuous configuration.
 3. A tubular pouch according to claim 1, wherein there are provided two stamped lines or other weaknesses of material, spaced apart from one another axially and each extending around the circumference of the tubular pouch body, which between them define a tear-open strip.
 4. A tubular pouch according to claim 1, wherein the weakness of material is formed close to the lid piece.
 5. A tubular pouch according to claim 1, wherein the weakness of material adjoins a cut formed at the free edge of the fin-seal.
 6. A tubular pouch according to claim 5, wherein the cut is in the form of a V-notch.
 7. A tubular pouch according to claim 1, wherein the lid piece is sealed or adhesively bonded to the tubular pouch body.
 8. A tubular pouch according to claim 1, further including at least one barrier layer selected from the group consisting of SiO₂, AlO_(x), ethyl vinyl alcohol or a metal foil.
 9. A tubular pouch according to claim 1, wherein the lid piece of relatively rigid construction and has sealable or adhesively bondable rims.
 10. A tubular pouch according to claim 9, wherein the lid piece is in the form of a shallow dish and is produced by deep-drawing or injection-molding.
 11. A tubular pouch according to claim 9, further comprising stand-up, standing or other base produced from a laminate and comprises a fold selected from the group consisting of a V-fold, and a W-fold.
 12. A tubular pouch according to claim 1, wherein a part(s) selected from the group consisting of said lid piece, said tubular pouch body, said lid piece and said tubular pouch body has/have a thickness selected from the group consisting of in the range of from 50μ to 500μ, especially from 80μ to 400μ, preferably from 100μ to 350μ.
 13. A tubular pouch according to claim 1, wherein a part(s) selected from the group consisting of said lid piece, said tubular pouch body, and said lid piece and said tubular pouch body is/are sterilisable.
 14. A tubular pouch according to claim 2, wherein at least the tubular pouch body comprises at least one unidirectionally stretched foil.
 15. A tubular pouch according to claim 15, wherein said unidirectionally stretched foil is part of a laminate.
 16. A tubular pouch according to claim 16, wherein the thickness of the unidirectionally stretched foil is greater than that of the remaining further layers of the laminate.
 17. A tubular pouch according to claim 15, wherein at least one unidirectionally stretched foil comprises material selected from the group consisting of at least one polyolefin, at least one polyamide, at least one ester, polyethylene, polypropylene, polyethylene terephthalate, and any two or more thereof.
 18. A tubular pouch according to claim 15, wherein the unidirectionally stretched foil has a thickness in selected from the group consisting of in the range of from 10μ to 200μ, from 35μ to 155μ, and from 45μ to 95μ.
 19. A tubular pouch according to claim 1, further comprising a stand-up, standing or other base.
 20. A tubular pouch according to claim 19, wherein a part(s) selected from the group consisting of said lid piece, said base, and said lid piece and said base is/are sealed or adhesively bonded to said tubular pouch body.
 21. A tubular pouch according to claim 1, wherein said tubular pouch body is produced from an aluminium or other laminate having at least one sealing layer.
 22. A tubular pouch according to claim 19, wherein a part(s) selected from the group consisting of said lid piece, said base, and said lid piece and said base are of relatively rigid construction and have sealable or adhesively bondable rims.
 23. A tubular pouch according to claim 19, further comprising a stand-up, standing or other base in the form of a shallow dish produced by deep-drawing or injection-molding.
 24. A tubular pouch according to claim 1, wherein said lid piece is produced from substantially the same materials as said tubular pouch body.
 25. A tubular pouch according to claim 19, wherein a part(s) selected from the group consisting of said lid piece, said base, said tubular pouch body, any two thereof, and all three thereof has/have a thickness selected from the group consisting of in the range of from 50μ to 500μ, from 80μ to 400μ, and from 100μ to 350μ.
 26. A tubular pouch according to claim 19, a part(s) selected from the group consisting of said lid piece, said base, said tubular pouch body, any two thereof, and all three thereof is/are sterilisable.
 27. A tubular pouch according to claim 20, wherein a part(s) selected from the group consisting of said lid piece, said base, and said lid piece and said base are produced from substantially the same materials as the tubular pouch body. 